Momentary enriching devices to improve the starting of internal combustion engines using fuel injection



Sept. 7, 1965 E. R, RUTENBER ETAL 3,204,524

MOMENTARY ENRICHING DEVICES TO IMPROVE THE STARTING OF INTERNAL COMBUSTION ENGINES USING FUEL INJECTION 2 Sheets-Sheet 1 Filed Aug. 15, 1963 NORMA N B. SCHAEFER ATTOR NEYS Sep 7, 1965 E. R. RUTENBER ETAL 3,204,524

MOMENTARY ENRICHING DEVICES TO IMPROVE THE STARTING OF INTERNAL COMBUSTION ENGINES USING FUEL INJECTION Filed Aug. 15, 1963 2 Sheets-Sheet 2 INVENTORS ELLWOOD R- RUTENBER NORMAN B. SCHAEFER AT TORN EYS United States Patent MOMENTARY ENRICHHNG DEVICES TO IMPROVE THE STARTING OF INTERNAL COMBUSTION ENGINES USWG FUEL INJECTION Ellwood R. Rutenher and Norman B. Schaefer, Wankesha, Wis., assignors to 'Waukesha Motor Company,

Waukesha, Wis., a corporation of Wisconsin Filed Aug. 15, 1963, Ser. No. 302,267 6 Claims. (Cl. 123-179) This invention relates to improvements in momentary enriching devices to improve the starting of internal combustion engines using fuel injection.

The general object of the present invention is to provide an improved device, applicable both on the conventional diesel engines and on ordinary engines having fuel injection, for causing momentary enriching to improve starting.

In conventional diesel engines it is customary for fuel pumps to be provided with full load stops which are for the purpose of limiting the fuel quantity for a maximum power setting. With the present invention the improved device is substituted for the usual full load stop and is so constructed that it performs its novel momentary enriching function as well as the full load' stop function.

A more specific object of the invention is to provide an improved device for use in connection with a fuel pump wherein there is means permitting movement of the fuel pump control rack to enriching position whenever the engine stops, to be ready for enrichment upon starting, and wherein oil pressure is utilized in a novel manner to promptly return the device to non-enriching or full load position as soon as the lubricating oil pressure is up to normal.

A more specific object of the invention is to provide an improved device as above described wherein a piston arrangement is utilized and wherein there is a spring for urging the piston to such a position, whenever the engine is out of operation, as to permit the parts of the mechanism to automatically assume an enriching position when the engine is dead, to thereby aid in starting, the arrangement being such that lubricating oil pressure acts on the piston to return it and the associated parts to non-enriching or full load position as soon as the lubricating oil pressure is up to normal after starting.

A further object of the invention is to provide a momentary enriching device as above described which is relatively simple in construction, inexpensive, and foolproof in operation.

With the above and other objects in view, the invention consists of the momentary enriching device and all of its parts and combinations, as set forth in the claims, and all equivalents thereof.

In the accompanying drawings, illustrating one complete embodiment of the preferred form of the invention, in which the same reference numerals designate the same parts in all of the views:

FIG. 1 is a fragmentary side elevational view of a diesel engine showing the improved device attached to the lefthand side of the fuel pump;

FIG. 2 is a fragmentary longitudinal sectional view showing the enriching device connected to the end of the control rack of the fuel pump;

FIG. 3 is a vertical cross-sectional view through a fuel pump of the type with which the present invention is used; and

FIG. 4 is a perspective view in longitudinal section showing a fuel pump plunger in one position of rotation in its sleeve.

Referring more particularly to the drawing, the nu meral designates a conventional diesel engine having "Ice a fuel pump 11. While the invention will be illustrated and described as particularly applicable to diesel engines, it is to be understood that the invention is also applicable to ordinary engines having fuel injection.

While the fuel pump illustrated is a conventional fuel pump, such as an American Bosch APE, it is necessary to briefly describe portions of the fuel injection pump to obtain a better understanding of the present invention. Any similar fuel pump having a fuel rack control may be utilized. The fuel injection pump is best shown in FIG. 3 and includes a chamber 12 for a cam shaft 13, which chamber also serves as a reservoir for the lubricating oil. The cam shaft has cams 14 which act on roller lifters 15 to cause reciprocation of the stems 16 of plungers 17.

As shown in FIG. 4, the plungers 17 have a lower helix 18 and a vertical slot 19, and below the helix is an annular groove 20. Each plunger operates in a barrel sleeve 9 having an inlet port 22 and a bypass port 23. This type of plunger gives a constant beginning of injection and a variable ending of delivery. The ports 22 u and 23 are closed on the upward stroke by the top edge of the plunger head. The time of opening the ports 22 and 23 is varied by the relation of the helix to the ports, as is well known in this type of injection pump, and this in turn is controlled by the position of rotation of the plunger head 17. Bypassing occurs when the helix uncovers the port. Bypassing also occurs when the vertical slot 19 is in registration with the bypass port 23.

Referring again to FIG. 3, the upper end of each control sleeve 21 is provided with an adjustable gear segment 21' which is operated by a horizontally reciprocating control rack 24. While longitudinal movement of the control rack may be manual in certain injection pumps, it is usually connected through linkage 25 and 26 (see FIG. 1) with a governor 27 so that the governor action causes reciprocation of the rack 24 in one direction or the other and resulting rotation of the plunger heads 17, through suitable connection between the control sleeves and plungers 16, to vary the quantity of fuel delivered by the injection pump, this fuel being forced out through the delivery valves 28 through conduits 29 connected with said valves, and leading to the injector nozzles in the combustion chambers of the engine 10.

Connected to the fuel injection pump 11 on the side opposite the governor is the improved enriching device 30. It is in a position in alignment with a projecting end of the control rack 24 as is clear from FIG. 7.. A lubricatthe oil line 31 leads from the oil gallery 32 of the engine, there being an oil conduit 33 leading to the gallery from the engine oil pump. The oil line 31 is connected to an inlet 34 of the casing 35 of the enriching device, which inlet is connected by a port 36 with the smaller diameter portion of the piston chamber 37, said smaller diameter portion being behind an annular stop shoulder 38. The piston 39 is fitted with a suitable O-ring 40 and has a rod 41 extending slidably therethrough, said rod having a threaded end 42 for receiving an adjustable full load stop nut 43. Said threaded end 42 projects into a cupshaped housing portion 44 for a spring 45. The spring acts on the piston 39 to urge it against the annular stop shoulder 38 when the engine is out of operation as will be hereinafter explained. The piston forms a movable abutment for the stop nut 43.

The opposite end of the stem 41 carries a head 46 with a projecting apertured lug 47 which is pivotally connected as at 48 to the end of the rack member 24 of the fuel injection device, there being a spring 49 acting in a lefthand direction on the head 46 to urge the parts toward shutoff position in case there should be a breakage or disconnection in the linkage 25-26 of the governor. Thus, the spring 49 is a safety feature.

Operation In operation, when the engine is operating, the fuel pump 11 normally pumps fuel through the outlet lines 29 to the usual injector nozzles in the combustion chambers of the engine 10. When the engine is dead, the spring 45 has urged the piston 39 to enriching position against the stop shoulder 38. This permits the governor spring 50 (see FIG. 1) to move the rod 41 and control rack 24 toward the right (referring to FIG. 2) to a point where the stop nut 43 abuts the piston 39. This movement of the rack 24 rotates the plunger head 17 to the full delivery or enriching position of the fuel injection pump, with the ducts 19 (FIG. 4) completely out of registration with the fuel ports. As soon as the engine starts, the lubricating oil pressure promptly reaches normal so that it can act through the line 31, inlet 34, and port 36 to move the piston 39 back to the full load position of FIG. 2. This causes return movement of the rack 24 to rotate the fuel pump plunger heads 17 to bring them into the full load position and stop the enrichment which previously took place for starting, and which occurred only when the piston was against the annular stop shoulder 38. It is thus apparent that the nut 43 acts as the full load stop which was previously used on fuel injection pumps prior to the present invention.

An important feature of the present invention, therefore, is the piston 39 which is automatically moved by the spring 45 to enrichment permitting position whenever the engine stops, said movement'taking place be- 9 cause the pressure of the lubricating oilin the line 31 is no longer acting in a reverse direction against the piston. This piston movement prepares the engine for enrichment whenever it is again started, the piston arrangement automatically providing for return of the rack 24 and control sleeves 21 to non-enriching position as soon as the lubricatingoil pressure is up to normal upon startig of the engine.

Various changes and modifications may be made without departing from the spirit of the invention, and all of such changes and modifications are contemplated as may come within the scope of the claims.

What we claim is:

1. In combination with an internal combustion engine having a fuel injection pump with means including a movable control member for metering the delivery of fuel to the engine and said engine having a pressure lubricating oil system, a momentary enriching device for improving starting of the engine comprising a piston rod having a pulley connection with said control member and having a full load stop thereon, spaced outwardly from said pulley connection, a fluid cylinder having .a piston therein through which an intermediate portion of said piston rod is slidable, said piston being located between said pulley connection .and full load stop and being movable in the cylinder from an enriching position to a full load position and forming a shiftable abutment for said full load stop, means normally urging said Piston to enriching position whenever the engine is dead, and a conduit connecting said pressure lubricating oil system of the engine to said cylinder in such a position as to automatically move the piston to full load position following starting of the engine, said piston being positioned to act on said full load stop during such movement to pull the piston rod and control member to full load position.

2. In combination with an internal combustion engine having a fuel injection pump with means including a movable control member for metering the delivery of fuel to the engine and said engine having a pressure lubricating oil system, a momentary enriching device for improving starting of the engine comprising a piston rod having a pulling connection with said control member and having a full load stop thereon spaced outwardly from said pulling connection, a fluid cylinder having a piston therein through which an intermediate portion of said piston rod is slidable, said piston being located between said pulling connection and full load stop and being movable in the cylinder from an enriching position to a full load position and forming a shiftable abutment for said full load stop, spring means acting only on said piston and normally urging said piston to enriching position whenever the engine is dead, and a conduit connecting said pressure lubricating oil system of the engine to said cylinder in such a position as to automatically move the piston to full load position following starting of the engine, said piston being positioned to act on said full load stop during such movement to pull the piston rod and control member to full load position.

3. In combination with an internal combustion engine having a fuel injection pump with means including a movable control member for metering the delivery of fuel to the engine and said engine having a pressure lubricating oil system, a momentary enriching device for improving starting of the engine comprising a piston rod having a pulling connection with said control member and having a full load stop thereon, a fluid cylinder having a main portion and having a smaller diameter portion with an annular shoulder between said portions, a piston through which an intermediate portion of said piston rod is slidable, said piston being located between said pulling connection and full load stop and being movable in the main portion of the cylinder from an enriching position against said shoulder to a full load position and forming a shiftable abutment for said full load stop, means normally urging said piston to enriching position against said shoulder whenever the engine is dead, and a conduit connecting said pressure lubricating oil system of the engine to said smaller diameter portion of the cylinder in such a position as to automatically move the piston to full load position following starting of the engine, said piston being positioned to act on said full load stop during such movement to pull the piston rod and control member toward full load position.

4. In combination with an internal combustion engine having a fuel injection pump with means including a movable control member for metering the delivery of fuel to the engine and said engine having a pressure lubricating oil system and having means normally urging said movable control member inwardly to enriching position, a momentary enriching device for improving starting of the engine comprising a piston rod having a pulling connection with and projecting from an end of said control member and having a full load stop nut adjustably threaded thereon and spaced outwardly from said pulling connection, a fluid cylinder having a piston therein through which said piston rod is slidable, said piston being located between said pulling connection and stop nut and being movable in the cylinder from an enriching position to a full load position and forming an abutment for said full load stop nut, spring means normally urging said piston to enriching position whenever the engine is dead to thereby permit independent movement of the movable control member inwardly to enriching position, and a conduit connecting said pressure lubricating oil system of the engine to said cylinder in such a position as to automatically move the piston to full load position following starting of the engine, said piston being positioned to act on said full load stop nut during such movement to pull the piston rod and control member to full load position.

5. For use with an internal combustion engine having a fuel injection pump with means including a movable control member for metering the delivery of fuel to the engine and having a projecting end normally urged inwardly to enriching position, and said engine having a pressure lubricating oil system, a momentary enriching device for improving starting of an engine comprising: a piston rod having an outer portion and having an inner end connectable to the projecting end of said movable control member to form a pulling connection therewith,

a full load stop member adjustably carried by an outer portion of said piston rod, a tubular casing having an inner portion connectable to the fuel pump to enclose said projecting end of the movable control member and its connection with the piston rod, said casing having an outer portion forming a fluid cylinder, a piston which is located inwardly of said full load stop slidable in said fluid cylinder and through which said piston rod is slidable, said piston being movable in the cylinder from an enriching position to a full load position and forming an abutment for the full load stop member, and means normally urging said piston inwardly to thereby permit independent movement of the movable control member inwardly to enriching position, said cylinder having a pressure port connectable with the pressure lubricating oil system of the engine and located in such a position as to provide for pressure movement of the piston to full load position following starting of the engine, said piston being positioned to act on said full load stop member during such movement to pull the piston rod and control member to full load position.

6. For use with an internal combustion engine having a fuel injection pump with means including a movable control member for metering the delivery of fuel to the engine and having a projecting end normall urged inwardly to enriching position, and said engine having a pressure lubricatin oil system, a momentary enriching device for improving starting of an engine comprising: a piston rod having an outer portion and having an inner end connectable to the projecting end of said movable control member to form a pulling connection therewith, a full load stop member adjustably carried by an outer portion of said piston rod, a tubular casing having an inner portion connectable to the fuel pump to enclose said projecting end of the movable control member and its connection with the piston rod, said casing having an outer portion forming a fluid cylinder, a piston which is located inwardly of said full load stop slidable in said fluid cylinder and through which said piston rod is slidable, said piston being movable in the cylinder from an enriching position to a full load position and forming an abutment for the full load stop member, means normally urging said piston inwardly to thereby permit independent movement of the movable control member inwardly to enriching position, said cylinder having a pressure port connectable with the pressure lubricating oil system of the engine and located in such a position as to provide for pressure movement of the piston to full load position following starting of the engine, said piston being positioned to act on said 'full load stop member during such movement to pull the piston rod and control member to full load position, and a cover for the stop member and portion of the piston rod which projects beyond the piston removably connected to an outer end of said casing.

References Cited by the Examiner UNITED STATES PATENTS 2,195,927 4/40 Hurst et a1. 123179 2,474,121 6/49 Sanders 123-139 2,879,754 3/59 Von Kienlin et a1. 123-198 FOREIGN PATENTS 529,672 11/40 Great Britain.

RICHARD B. WILKINSON, Primary Examiner. 

1. IN COMBINATION WITH AN INTERNAL COMBUSTION ENGINE HAVING A FUEL INJECTION PUMP WITH MEANS INCLUDING A MOVABLE CONTROL MEMBER FOR METERING THE DELIVERY OF FUEL TO THE ENGINE AND SAID ENGINE HAVING A PRESSURE LUBRICATING OIL SYSTEM, A MOMENTARY ENRICHING DEVICE FOR IMPROVING STARTING OF THE ENGINE COMPRISING A PISTON ROD HAVING A PULLEY CONNECTION WITH SAID CONTROL MEMBER AND HAVING A FULL LOAD STOP THEREON, SPACED OUTWARDLY FROM SAID PULLEY CONNECTION, A FLUID CYLINDER HAVING A PISTON THEREIN THROUGH WHICH AN INTERMEDIATE PORTION OF SAID PISTON ROD IS SLIDABLE, SAID PISTON BEING LOCATED BETWEEN SAID PULLEY CONNECTION AND FULL LOAD STOP AND BEING MOVABLE IN THE CYLINDER FROM AN ENRICHING POSITION TO A FULL LOAD POSITION AND FORMING A SHIFTABLE ABUTMENT FOR SAID FULL LOAD STOP, MEANS NORMALLY URGING SAID PISTON TO ENRICHING POSITION WHENEVER THE ENGINE IS DEAD, AND A CONDUIT CONNECTING SAID PRESSURE LUBRICATING OIL SYSTEM OF THE ENGINE TO SAID CYLINDER IN SUCH A POSITION AS TO AUTOMATICALLY MOVE THE PISTON TO FULL LOAD POSITION FOLLOWING STARTING OF THE ENGINE, SAID PISTON BEING POSITIONED TO ACT ON SAID FULL LOAD STOP DURING SUCH MOVEMENT TO PULL THE PISTON ROD AND CONTROL MEMBER TO FULL LOAD POSITION. 